A compound represented by the following formula (X) [hereinafter, also referred to as compound (X)] or a pharmacologically acceptable salt thereof, or a hydrate thereof is a compound that exhibits an FXa inhibitory effect, as disclosed in Patent Literatures 1 to 3, and is useful as a preventive and/or therapeutic drug for thrombotic and/or embolic diseases:

The pamphlet of International Publication No. WO 2007/032498 discloses a process for preparing an FXa inhibitor compound (X) or a pharmacologically acceptable salt thereof, or a hydrate thereof. The process for producing compound (X) disclosed therein involves, as shown in [Scheme A] below, azidifying compound (2) to produce azide compound (3), subsequently reducing compound (3) into amino compound (1a), subsequently treating compound (1a) with anhydrous oxalic acid to obtain compound (1), which is then treated with compound (4) (ethyl 2-[(5-chloropyridin-2-yl)amino]-2-oxoacetate monohydrochloride) in the presence of a base to produce compound (5), followed by several steps from compound (5). This pamphlet also discloses crystals of the oxalate of compound (1) as a production intermediate.
wherein Boc represents a tert-butoxycarbonyl group.